1. Field of the Invention
The present invention relates to a radio frequency identification tag apparatus for a tire in a radio frequency identification system (hereinafter, referred to as a ‘RFID system’), and more particularly to, a radio frequency identification tag apparatus for a tire.
2. Description of the Background Art
Recently, the ubiquitous RFID technology is rising. The term ‘ubiquitous’ means a radio communication environment where a user can access freely to a network regardless of location without being conscious of a computer or network. The RFID is a key factor which becomes a clue to the ubiquitous computing revolution, which enables to send and receive data on the history of items necessary for daily life, commodities, etc. by embedding radio chips, instead of conventional barcodes, for storing the history of the items or commodities in the items or commodities. Thus the RFID is applicable to the history, distribution, inventory control, burglarproof, etc. of every items and commodities.
Especially, one example of the fields the RFID is applicable to may include a tire. The RFID is mounted to tires of an automobile, and it not only can be applied to the history, distribution, inventory control, burglarproof, etc. of a tire, but it may also settle disputes which may be raised upon occurrence of an accident caused by the tire.
The RFID system applicable to tires is comprised of an RFID tag (or transponder) storing even characteristic information of a tire in the tire, an RFID reader for executing the functions of reading and decoding the characteristic information of the tire, a host computer, a network and an application program.
FIG. 1 is a view showing a general radio frequency identification tag apparatus. FIG. 2a is a front view of a tire in case a general radio frequency identification tag for a tire is inserted into the tire. FIG. 2b is a front perspective view of a tire in case a general radio frequency identification tag is inserted into the tire. Hereinafter, an RFID tag apparatus applicable to a tire and a method of inserting the same into a tire will be described with reference to FIGS. 1 and 2.
Reference numeral 10 in the drawings is a RFID tag. The RFID tag 10 comprises a radio chip 1, an antenna 2 and a flexible substrate 3.
The antenna 2-1 and 2-2 creates a radio frequency signal transmitted from a reader to provide it to the radio chip 1, and transmits a radio signal outputted from the radio chip 1 into midair. Typically, the above radio frequency signal is a radio frequency in an ultra high frequency band The radio chip 1 is provided with a memory storing characteristic information for the history, distribution, inventory control, etc. of a tire, receives a radio frequency signal from the antenna 2-1 and 2-2 and rectifies it, modulates the characteristic information of the tire by the rectified voltage and outputs them to the antenna 2-1 and 2-2 in the radio signal transmitted from the reader. The radio signal transmitted through the antenna 2-1 and 2-2 is transmitted to a reader. The re-transmission of characteristic information in a radio frequency signal transmitted from the reader is generally referred to as backscattering.
The RFID tag 10 for a tire thus constructed is inserted into a tire 20 as shown in FIGS. 2a and 2b. It is preferable that the RFID tag 10 is arranged at a location that is not affected by the friction of the tire 20 and not bent by the curve of the tire 20. Further, it is preferable that the RFID tag is inserted so as not to move within the tire 20.
However, the tire 20 is made of rubber while the RFID tag 10 is constructed as a case made of resin or a flexible substrate 3 as shown in FIG. 1. Therefore, since the RFID tag 10 to be mounted within the automobile tire 20 is constructed of an essentially different medium with the material of the tire, its adherability with the tire 20 of rubber becomes lowered. For this reason, only a two-dimensional barcode is currently being touched as a technique practically applicable at a site.
As described above, since the tire and the RFID are constructed of a different heterogeneous medium, this leads to a problem that the adherability between the tire and the RFID tag becomes lowered.
Further, because the adherability between the tire and the RFID tag is lowered, this may bring about a secular change in the apparatus aspect, such as a change of a metallic antenna or substrate. Resultantly, this may lead to the deterioration of RF characteristics which can be referred to as the index of RFID performance.
Further, due to an apparatus problem that the tire is lack of an element playing the role of supporting except for rubber layers surrounding the tire, there is a high possibility that the stimulus of a heterogeneous medium will be applied to the rubber layers as the RFID tag is shifted within the tire, which may bring about a defect such as a tire burst.